prep 1- unit 2- LESSON 2 - energy transformations - الصف الأول الاعدادي - علوم - science - 2023 скачать в хорошем качестве

prep 1- unit 2- LESSON 2 - energy transformations - الصف الأول الاعدادي - علوم - science - 2023

الصف الأول الاعدادي الفصل الدراسي الاول المنهج الجديد ساينس أول إعدادي المنهج الجديد الصف الأول الإعدادي علوم لغات 2023 Science 1 st prep , lesson 1 شرح ساينس المنهج الجديد 1 st prep science للصف الأول الإعدادي 2023‪ الترم الأول الفصل الدراسي الأول Scienceالمنهج الجديد علوم ساينس الصف الأول الإعدادي 2023‪ ساينس أولى إعدادي المنهج الجديد 1 st prep science, Science , 1 st prep lesson , science الاول الاعدادي science ,1 st prep , first term ,unit 1, lesson 1 منهج الصف الأول الإعدادي الجديد 2023 منهج الصف الأول الإعدادي الجديد 2023 المنهج الجديد الصف أولى إعدادي المنهج الجديد للصف الأول الإعدادي 2023 منهج أولى الإعدادي الجديد الأول الإعدادي المنهج الجديد أولى إعدادي 2023 المنهج الجديد الصف الأول الإعدادي منهج الصف 1st prep 2023 منهج الصف الرابع الابتدائي الجديد ملامح الجديد , علوم , شرح مفصل , فيديو تعليمي , تدريبات دروس , منهج منهج الصف 1st prep unit 2 : تحولات الطاقة energy transformation potential energy, kinetic energy and mechanical energy First : potential energy When pulling a string of an arc (change its position), the work done to pull this string is stored in it in the form of potential energy. Potential energy : It is the energy stored in the object due to the work done on it. What is meant by ...? The potential energy of an object = 40 joule. This means that the energy stored in the object due to work done on it is 40 joule. Factors affecting the potential energy: 1. Weight of the object. w = m (mass) x g ( gravity acceleration ) 2. Height of the object from the ground. h Weight of the object Activity (1) To show the effect of the weight of the object on its potential energy: Steps : 1. Bring four identical spheres and let them be on the ground . 2. Lift one sphere from the ground up to a table level. 3. Lift two spheres (together) up to the same level of the table. 4. Repeat the previous step by lifting up three spheres, then four spheres. Observation : The work (effort) done to lift spheres up increases by increasing the number of lifted spheres (the weight). Conclusion : The potential energy stored in an object increases by increasing its weight. Weight(Newton) = Mass (kg) X Acceleration due to gravity (m/sec2) The value of the acceleration due to gravity = 9.8 or 10 m/sec2 . G.R. The weight of an object is different from its mass. Because object's weight = Object's mass x Acceleration due to gravity. 2 . Height of the object from the ground Activity (1) • To show the effect of the height of the object from the ground on its potential energy: Steps : 1. Bring a basin filled with sand and a somewhat heavy sphere. 2. Raise the sphere a half meter height and let it fall in the basin. 3. Repeat the previous step several times by increasing the height of the sphere and returning the sand graded every time. Observation : (Joule) = ( Newton ) x ( Meter ) To calculate the potential energy, Weight and Height : Potential energy = P.E. = W X h Weight = P.E./ h Height = P.E./ h NB : Work = Force x Displacement • When the work is stored in a form of potential energy notice that : Force is indicated by the weight. Displacement is indicated by the height from the Earth's surface. What is meant by ...? The potential energy of an object = zero. This means that the object is placed on the ground. G.R. No change in the potential energy when the object moves horizontally. Because its height does not change as the potential energy is directly proportional to the height of the object from the ground. Problems 1- An object, whose mass is 2.5 kg. and it is at a height of 4 m., calculate its potential energy. If its height is decreased by 1 m., calculate its new potential energy. (Acceleration due to gravity = 10 m/sec). Solution .Weight = Mass x Acceleration due to gravity = 2,5 x 10 =250 N . P. E. at a height of 4 m. = Weight x Height = 25 x 4 = 100 joule When the height decreases by 1 m., the new height will be 3 m. New potential energy = 25 x 3 = 75 joule . 2 - Find the weight of an object of potential energy 88 joule when it is found at a height 11m. Solution Weight = Potential energy / Height = 88 / 11 = 8 N . Question 1. An object, whose mass is 2 kg. and it is at a height of 5 m. from the Earth's surface. Calculate the potential energy. Solution 2. Calculate the height of an object from the Earth's surface. Knowing that its weight is 4 N and its potential energy is 10 joule. What happens to the potential energy in the following cases Numerical application ( Potential energy = Weight x Height ) 1- If the weight of an object increases to double «height is constant». The potential energy increases to double. By increasing the height of the sphere upwards, the work done increases, therefore the print that the sphere makes in the sand increases by increasing its height from the ground. Conclusion : the potential energy increases by increasing the height at which the object reaches